This project encompasses a wide scope of statistical collaboration and consultation with Laboratories and Branches within the Division of Intramural Research (DIR), and with other units outside of NIH. Particular consideration is given to statistical planning and design of experiments, statistical analysis of data, and statistical inference. Our collaboration has involved seven Laboratories/Branches, and the scope of the studies has ranged from the coordination and statistical management of clinical trials to consultation on the appropriateness of the statistical analysis used for small laboratory experiments. Examples of studies with DIR include: randomized clinical trials of felbamate for the treatment of intractable complex partial seizures (MN); development of time series models for the effect of weather and ambient light on mood in patients with seasonal affective disorder (NIMH); measurement of the effect of time from last seizure and seizure type on the dynamics of inter-ictal; metabolic change (MN); clinical trial of predisone for the treatment of post polio muscle atrophy (MN); optimal sampling procedures to estimate the size of a population of neuron cells (CN); identification of risk factors for febrile seizures with a population based case-control study of six cities in China (NE); statistical analysis of shape and spatial relationships of maps of the cerebral cortex based on EMG responses to electromagnetic stimulation of the scalp (MN) ; clinical course and outcome of patients with Gaucher's disease (DMN) ; clinical evaluation of Ceredase(TM) glucocerebrosidase in Gaucher's diseases (DMN) ; prevalence of neurological diseases in the Navajo tribe (MN); use of quasi-likelihood models to demonstrate that seizure frequencies are not random in time (MN) ; study of epilepsy progression to general tonic-clonic seizures (MN) ; and the use of hyperarousal scores for diagnosis of chronic insomnia (MN).